This invention relates generally to the art of power toothbrushes and more specifically concerns a system for indicating when a brushhead portion of a power toothbrush should be replaced.
It is generally agreed that toothbrushes are not replaced as frequently as is usually recommended by dentists. This includes the removable brushhead portion of power toothbrushes. Such brushheads can wear out to the point of significant reduction in effectiveness, but may not show any obvious signs of wear, or obvious indication of performance deterioration. Reduced brush effectiveness, of course, is undesirable relative to maintaining good dental health.
There have been various attempts to address the failure to replace brushheads in timely (and healthy) fashion by the use of dye impregnated bristles or a colored bristle sheath, which are both capable of showing signs of wear. The indication of wear by such structural means, however, is not precise and hence may not provide definitive guidance to the user as to when the brushhead should be replaced.
Hence, there is a need for a system of precisely and clearly indicating to the user when a brushhead should be replaced so as to maintain high level of brushing performance and effectiveness.
Accordingly, the present invention is a system for determining automatically when a brushhead portion of a power toothbrush should be replaced and for providing an indication thereof to the user, comprising: A system carried within the toothbrush for detecting and accumulating the number of occurrences of a characteristic directly related to actual use of the toothbrush; means for determining when the number of said occurrences of said characteristic of toothbrush use reaches a preselected number, said preselected number correlating to sufficient use of the brushhead that the brushhead should be replaced; and an indicator, such as a visual or audible alarm, for communicating to the user that the brushhead should be replaced.